str1 ="hello world"
str2 ='hello world'
str3 ='''hello world'''
print(str1)
print(str2)
print(str3)
print('hel\lo world')
print('123---{0}'.format(4))
str1='hello'
print(f'123---({str1}')

for i in range(0, 101, 2):
    print("=========开始下载=========")
    if i == 100:
        print("下载完成")
    else:
        str4 = "*" * (i // 2) + "." * ((100 - i) // 2)
        print(f'{i}%[{str4}]')





